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Patent Treuhand Gesellschaft Fur Elektrische Gluhlampen Mbh

Patent-treuhand-gesellschaft F. Elektrische Gluehlampen Mbh

Patent-treuhand-gesellschaft Fuer Elektrische Gluehlampen Mbh

Patent-treuhand-gesellschaft Fur Elektrisch Gluhlampen Mbh

Josef Osterried

Andreas Huber

Alwin Veser

Peter Niedermeier

Franz Bernitz

Frank Hansmann

Wolfram Graser

Markus Haederle

Elisa Garavini

A circuit configuration for operating at least one LED, comprising: an input with a first input terminal (E) and a second input terminal (E) for coupling to a DC voltage supply (U); an output having a first output terminal (A) and a second output terminal (A) for providing an output current (IA) to the at least one LED; a micromirror arrangement () comprising a plurality of micromirrors; a first control device () configured for providing, at the output thereof, a first control signal (S) for the micromirror arrangement (), the first control signal (S) being synchronized to a first clock frequency (fc); a switching regulator (), the input thereof being coupled to the first input terminal (E) and the second input terminal (E), and the output thereof being coupled to the first output terminal (A) and the second output terminal (A), the switching regulator () comprising a switch (S); and a second control device () configured for providing, at the output thereof, a second control signal (Sb) for the switch (S) of the switching regulator (); wherein the second control signal (S) is synchronized to a second clock frequency (f), wherein the equation f=n*fapplies, where n&#x3b5;.

Circuit configuration for operating LEDs for a micromirror arrangement

A circuit arrangement may include an input for coupling to a supply voltage; n semiconductor light source units comprising a driver device; wherein the units are coupled in parallel, wherein each driver device comprises a PWM controller. A respective controller is designed to provide a PWM signal at a respectively predefinable frequency to a control electrode of a respective converter switch. The arrangement includes current measuring devices which are designed for measuring the current through a respective string having at least one semiconductor light source; and a control device having control outputs, wherein each controller has a clock input, wherein a respective control output is coupled to a respective clock input of the controllers, wherein the control device is designed to provide clock signals at its control outputs, said clock signals being phase-shifted by 360&#xb0;/n with respect to one another.

Circuit arrangement for operating N parallel-connected strings having at least one semiconductor light source

An electronic ballast for a lamp () having an input circuit () having a connection to a voltage supply, an output circuit () having a connection for the lamp (), and a voltage converter apparatus (), which is arranged between the input and the output circuit (), the voltage converter apparatus including an input capacitor (C) and an output capacitor (C), between which a switching apparatus (T) and a freewheeling diode (D) as well as at least one damping element (L), at least one trapezoidal capacitor (C) and an inductance (L) are arranged, the voltage converter apparatus () being designed to carry out commutation, in each case a main circuit being defined by the current flow prior to and following commutation, at least one damping element (L) and at least one trapezoidal capacitor (L) being connected in series, and such a series circuit being arranged in a secondary circuit.

Electronic ballast with voltage converter having improved damping arrangement

Flickering phenomena in gas discharge lamps are undesired in projection technology, in particular. According to the invention, the problem is solved by setting a lamp operation which does not form a focal spot. A specific control structure which includes a cascade structure and feedforward control is proposed for implementing this operation.

Stabilizing the operation of gas discharged lamps

The circuit for operating a high-pressure gas discharge lamp (HID) has a ice (ZZU) for ignition-time bridging by switching in a second lamp (GL), the ignition-time bridging device (ZZU) being driven by a signal (S) indicating the operating state of the high-pressure discharge lamp (HID), and the drive signal (S) being an output signal of a power controller (R) of the circuit.

Operating circuit for high-pressure discharge lamps with an

To largely, or entirely inhibit glow discharges during the start-up or run-on phase (Ta) of a high-pressure discharge lamp, the lamp is operated in a second time period (T2) immediately after ignition (T1) with continuous direct current during which the electrode of the lamp which then functions as an anode has reached emission temperature; in a third time period (T3), the polarity of the direct current is reversed and the other electrode, which now will function as an anode, is heated to emission temperature; thereafter, alternating current energy is supplied to both electrodes, typically in frequencies between 90 and 150 Hz. A suitable second time period (T2) can be about 2 to 21/2 second, the third time period (T3) being shorter. The total warm-up time may extend to a minute or more; current being supplied during the second, third and subsequent periods is usually higher, for example by a factor of 1.5 of the normal or rated operating current.

Ignitional run circuit that immediately applies only a DC voltage after

An auxiliary or ballast circuit for high-frequency operation of discharge mps (E), for example sodium high pressure discharge lamps, provides for controlled inrush or 'ON current' by including a thyristor (TH1) or pair of thyristors (TH2, TH3) in the current supply path to the discharge lamp (E) integrated into a combination active filter-voltage step-up circuit. The gate of the thyristor (TH1) or a pair of thyristors (TH2, TH3) is, or are, controlled over a resistance (R2, R3, R4) connected to the output capacitor (C2) of the filter-voltage step-up circuit to fire the thyristor when input voltage goes through null, and the output capacitor (C2) has a predetermined voltage level above the input voltage. The output capacitor (C2), before firing, is charged by a charge control resistor (R1) connected in parallel across the anode-cathode path of the thyristor or thyristors. Thus, a maximum controlled inrush current is provided independent of ambient temperature or temperature of a NTC resistor and not requiring a relay.

High frequency operating circuit with in-rush current protection for

To permit, selectively and in accordance with safety or standardization rirements, connection of different electrical supply devices, such as extending cables or terminal posts, pins or clamps, to a single, standardized operating or accessory circuit retained on a circuit board (2) within a housing (1), the housing is formed with a connection receiving portion (5a) selectively differently constructed connection parts (3, 3') forming insert elements are provided, dimensioned and shaped to fit into the receiving portion of the housing. The connection parts, forming the insert element, thus can be constructed according to the respective safety or standardization requirements without otherwise affecting the structure of the substantially more expensive operating or accessory circuit in the housing. A strain relief can be integrated with the construction, for example secured to the housing and/or the connection part to clamp wires or cables projecting from the housing, attached to terminal pins, posts or clamps of one form of connection part, or directly from another form of connection part.

Growing community of inventors

Ottobrunn, Germany

Josef Osterried